From 887f3ceb51cd34109ac17bfc98695162e299e657 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 19 Mar 2021 11:06:58 +0000 Subject: powerpc/signal32: Convert do_setcontext[_tm]() to user access block Add unsafe_get_user_sigset() and transform PPC32 get_sigset_t() into an unsafe version unsafe_get_sigset_t(). Then convert do_setcontext() and do_setcontext_tm() to use user_read_access_begin/end. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/9273ba664db769b8d9c7540ae91395e346e4945e.1616151715.git.christophe.leroy@csgroup.eu --- arch/powerpc/kernel/signal.h | 2 ++ arch/powerpc/kernel/signal_32.c | 42 +++++++++++++++++++++++------------------ 2 files changed, 26 insertions(+), 18 deletions(-) diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h index a5152ff3c52f..f4aafa337c2e 100644 --- a/arch/powerpc/kernel/signal.h +++ b/arch/powerpc/kernel/signal.h @@ -25,6 +25,8 @@ static inline int __get_user_sigset(sigset_t *dst, const sigset_t __user *src) return __get_user(dst->sig[0], (u64 __user *)&src->sig[0]); } +#define unsafe_get_user_sigset(dst, src, label) \ + unsafe_get_user((dst)->sig[0], (u64 __user *)&(src)->sig[0], label) #ifdef CONFIG_VSX extern unsigned long copy_vsx_to_user(void __user *to, diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 0b1a6f53e553..592b889e3836 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -83,12 +83,7 @@ * implementation that makes things simple for little endian only) */ #define unsafe_put_sigset_t unsafe_put_compat_sigset - -static inline int get_sigset_t(sigset_t *set, - const compat_sigset_t __user *uset) -{ - return get_compat_sigset(set, uset); -} +#define unsafe_get_sigset_t unsafe_get_compat_sigset #define to_user_ptr(p) ptr_to_compat(p) #define from_user_ptr(p) compat_ptr(p) @@ -144,10 +139,7 @@ failed: unsafe_copy_to_user(__us, __s, sizeof(*__us), label); \ } while (0) -static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset) -{ - return __get_user_sigset(set, uset); -} +#define unsafe_get_sigset_t unsafe_get_user_sigset #define to_user_ptr(p) ((unsigned long)(p)) #define from_user_ptr(p) ((void __user *)(p)) @@ -982,25 +974,31 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sigset_t set; struct mcontext __user *mcp; - if (get_sigset_t(&set, &ucp->uc_sigmask)) + if (user_read_access_begin(ucp, sizeof(*ucp))) return -EFAULT; + + unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed); #ifdef CONFIG_PPC64 { u32 cmcp; - if (__get_user(cmcp, &ucp->uc_regs)) - return -EFAULT; + unsafe_get_user(cmcp, &ucp->uc_regs, failed); mcp = (struct mcontext __user *)(u64)cmcp; } #else - if (__get_user(mcp, &ucp->uc_regs)) - return -EFAULT; + unsafe_get_user(mcp, &ucp->uc_regs, failed); #endif + user_read_access_end(); + set_current_blocked(&set); if (restore_user_regs(regs, mcp, sig)) return -EFAULT; return 0; + +failed: + user_read_access_end(); + return -EFAULT; } #ifdef CONFIG_PPC_TRANSACTIONAL_MEM @@ -1014,11 +1012,15 @@ static int do_setcontext_tm(struct ucontext __user *ucp, u32 cmcp; u32 tm_cmcp; - if (get_sigset_t(&set, &ucp->uc_sigmask)) + if (user_read_access_begin(ucp, sizeof(*ucp))) return -EFAULT; - if (__get_user(cmcp, &ucp->uc_regs) || - __get_user(tm_cmcp, &tm_ucp->uc_regs)) + unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed); + unsafe_get_user(cmcp, &ucp->uc_regs, failed); + + user_read_access_end(); + + if (__get_user(tm_cmcp, &tm_ucp->uc_regs)) return -EFAULT; mcp = (struct mcontext __user *)(u64)cmcp; tm_mcp = (struct mcontext __user *)(u64)tm_cmcp; @@ -1029,6 +1031,10 @@ static int do_setcontext_tm(struct ucontext __user *ucp, return -EFAULT; return 0; + +failed: + user_read_access_end(); + return -EFAULT; } #endif -- cgit v1.2.3